Wear distributor for suction-roll shells



0d. 8, 1929. FARNSWQRTH 1,730,921

WEAR DISTRIBUTOR FOR SUCTION ROLL SHELLS Filed Aug. 11, 192a s Sheets-Sheet 1 ,INVENTOR my? ATTORNEY Oct. 8, 1929. H. R. FARNSWORTH 1,730,921

WEAR DISTRIBUTOR FOR SUCTION ROLL SHELLS Filed Aug. 11. 1928 5 Sheets-Sheet 2 ATTORNEY Oct. 8, 1929. H. R. FARNSWORTH WEAR DISTRIBUTOR FOR SUCTION ROLL SHELLS Filed Aug. 11, 1928 5 Sheets-Sheet N ME ENTOR BY flM ATTORNEY Patented Oct. 8, 1929 UNITED STATES PATENT OFFICE HILAND IR. FARNSWORTH, OF SANDUSKY, OHIO, ASSIGNOR TO THE PAPER & TEXTILE MACHINERY COMPANY, OF SANDUSKY, OHIO -WEAR DISTRIBUTOR FOR- SUCTION -ROLL SHELLS Application filed August 11, 1928. Serial No. 298,969.

The present invention relates to pa er making machinery and more particu arly to means for distributing uniformly over the inner surface of the suction roll the wear on its surface by the suction box packing or, briefly, to a wear distributor for suction rolls.

In modern paper making machines, suction rolls are an important part of the construction. These rolls, as is well known, are revoluble metal cylinders perforated by a great number of closely disposed small dianieter bores, the intervening irregularly shaped portions constituting the walls of the suction roll. Within this cylinder is mounted the suction box or chamber which is closed on all sides except that exposed to a comparatively narrow segment extending longitudinally of the roll for a distance equal to the width of the sheet to be formed. This is the suction area, or that part through which air is evacuated to withdraw a portion of the Water from the pulp on the wire or other support, which is continuously passing over the cylinder, and at the same time interlock and set or bind the fibers in the first part of the sheet forming process. In order to prevent leakage and loss of vacuum, adjustable segmental deckels towards the ends of the cylinders, and longitudinal packing strips along the edges of the suction chamber or box are provided, making a substantially airtight joint completely around the open side of the suction box or chamber. Due to the partial vacuum in the chamber, the packing strips and deckels rub against the inner wall of the cylinder to a greater or less degree, set screws or other well-known adjusting devices being used to prevent locking of the box or chamber to the cylinder and to regulate the contact between them. Since there is no relative movement between the packing strips and cylinder wall, other than the revolving movement of the cylinder, there is a tendency to wear irregularly, causing a grooved or scored surface in the inner wall of the cylinder. Such scoring or irregular wearing soon renders the cylinder ineffective or partially inoperative through leakage and loss of suction. Of course, regrinding of the inner wall to a uniform diameter involves heavy expense. In addition, new packing strips would have to be provided and the loss of time for these repairs is a heavy item. It is the purpose of the present invention to eliminate this defect and provide a cylinder in which there will be a uniform and even distribution of wear, throughout, maintaining a smooth and regular surface, and a substantially airtight joint between the cylinder and packing at all times. y

In order to more clearly disclose the construction, operation and use of the invention, reference should be had to the accompanying drawings forming part of the present application. 'lhroughout the several figures of the drawings like reference characters designate the same parts in the different views.

In the drawings:

Fig. 1 is a top plan view of a preferred fofim of the invention, as applied to a suction r0 Fig. 2 is a cross section on line 2-2 of Fig. 1;

Fig. 3 is a top plan view of another form of the invention Fig. 4; is across Fig. 3; t I Fig. 5 is an enlarged fragmentary longitudinal cross section through part of the shell wall, to which the invention has not been ap plied;

Fig. 6 is a like view of a shell to which the invention has been applied.

Fig. 7 is a top plan view of a further form of the invention.

F Fig. 8 is a cross section on line 88 of As shown in the two forms of the invention illustrated, the shell or roll is moved longitudinally relatively to the suction box. The result will be the same, of course, if the box is moved longitudinally, relatively to the cylinder or shell. The substance of the invention is the same whether the shell or the box is moved. The meat of the invention, is a means of effecting relative longitudinal movement between the shell and the box to cause a uniform distribution of the wear and avoid scoring. It is, likewise, obvious that many section of line 4-4 of end of the roll and other different constructions and dispositions of the operating parts may be resorted to without in any sense departing from the real essence and meaning of the invention.

In the form shown in Figs. 1 and 2, cam surfaces carried by stationary hearings or other members adjacent one end of the revoluble cylinder are engaged by suitable pro]ections carried by the gear on the cylinder end. Of course, a collar or flange could be disposed and operated in the same way.

In the form shown in Figs. 3 and 4 oppositely acting gear-driven eccentrics are used. These are actuated by a star wheel or other element actuated by the suction roll, gear or corresponding member. The general idea s the same. However, one advantage of this second form is that the gears and star wheel may be so proportioned and arranged as to cause one reclprocation of the longitudinally movable member for each revolution of the shell, as in the first form, or to cause a greater or a less number of such reciprocations per revolution, as may be desired. While the form of Figs. 1 and 2 may be simpler and of somewhat lower cost, that of. Figs. 3 and 4 has a somewhat wider range of use.

Such modifications and changes in detail, as may be necessary to adapt the constructions shown to reciprocation of the suction box or inner element instead of the shell or outer element, involve the same general idea and are a part of the same invention. It is not thought necessary or as in any way adding to the clearness to the disclosure of the invention to illustrate or describe these reversals of parts. In the comparative drawings, Figs. 5 and 6, it is understood, of course, that the grooving or scoring on the inner face of the cylinder wall is considerably magnified in order to more clearly show the defects of the old arrangement. Scoring which is hardly noticeable to the naked eye is sufficient to cause heavy leakage between the packing strips and wall, with corresponding decrease in vacuum. In Figs. 1 and 4 of the drawings only one its supports has been shown. It will he understood, of course, that the opposite end is similarly mounted as is the regular and uniform practice in this class of machines. The device or mechanism for causing reciprocation is, most'conveniently, disposed at one end only. Obviously t may be duplicated at each end. Or, the mechanism may be distributed, that for moving in one direction at one end with the reverse at the opposite end. Therefore, one end, only, need be illustrated. In the preferred form, shown in Figs. 1 and 2, either a forked or two-armed standard, or two separate spaces, and parallel standards, may be used for the mounting and support of the cylinder end. Separate standards are here shown. Each standard 1 is provided with the usual cylindrical bearing 2 to freely receive the end of the suction roll or shell 3. On the inner face of each standard, substantially concentric with the bearing 2 and extending completely around said bearing, is a circular cam 4-. of gradually increasing height or pitch, from end to end, the two cams being inclined or pitched in the same direction and, therefore, when facing each other, as in this case, acting oppositely on any element simultaneously engaged by them from opposite sides. Between these two cams the usual driving gear 5 is secured to the shell 3, its thickness being such as to enable a certain limited amount of free longitudinal movement between the standard ends. From opposite faces of the gear pro ject small studs, rounded pins, or like engaging elements 6 which are adapted to travel in continuous contact with the cams 4. Instead of pins or studs, cooperating cam surfaces on the gear may be provided. In fact the cooperating cam surfaces have the advantage of more evenly distributing wear between contact surfaces and more regular and uniformly even sliding movement of the other. Likewise, with cooperating cams on the gear faces, there is a more solid and compact construction, the gear and standards continuously bracing each other throughout the rotation and the sliding movement of the gear and cylinder. There will be a continuous contact surface throughout the lengths of the cooperating cams.

Of course, if the shell were driven by a clutch or by gear but from some other point. a collar, flange, or the like, in the same posi tion as the gear 3 would Work in exactly the same way. It is necessary, of course, to have the cylinder or shell slidably mounted in its bearings. Any Well known sliding mounting may be used, as it is only necessary to provide for reciprocation of the shell during its regular revolution.

At the same time the suction box will, of course, be held, as usual, so that it will not move with the shell, either longitudinally or circumferentially. Such construction being general and well known, it is not necessary to illustrate the same in this case.

In the form shown in Figs. 3 and 4 eccentrics entirely independent of the standards and gear, but operating on the gear, are substituted for the cam or cams and cooperating pins. In the construction shown in this form a short shaft 7 is suitably journaled in a small bracket or the like 8 and carries a small bevel gear 9 at its upper end. This is duplicated on the inner face of the upper end of each standard. A small drive shaft 10 is journaled in small brackets 11 on the upper ends of the standards and carries at its opposite ends, bevel gears 1-2 which mesh. with and drive the gears 9 and their shafts 7. On the lower ends of the shafts 7 are securely fixed eccentrics 13 which are oppositely dislit posed (180 of rotation apart) and engage opposite faces of the gear 5 which is fixed to and drives shell 3. To the shaft 7 is secured asuitable driving means actuated bfy the shell driving gear or by the rotation o the shell itself. Preferably, this driving connection between the shaft 7 and gear 5 comprises a star wheel 14 fixed to the shaft 10 and actuated by a pin or other suitable projection 15. In this arrangement, a single pin is carried by -.gear 5 so that each complete revolution of the shell will rotate the shaft 10 only the distance corresponding to one tooth of the star wheel. In this way, the number of rotations of the eccentrics may be regulated as desired. It is only necessary to vary the number of pins 15 on the gear 5 or the number of arms on the star wheel, 14 or both, to

get the desired number of rotations of the eccentrics relatively to a single revolution of the cylinder.

As will be clear from the drawings, the eccentrics are so designed and positioned, that both are continuously in contact with the adjacent wall or face of gear 5, or corresponding element, and the beveled gears are so intermeshed that the contacting surface of the eccentrics will travel or rotate in the same direction as gear 5, thereby avoiding unnecessary friction. Likewise, of course, they'will. necessarily, rotate in opposite directions. This, of course, gives a steady sliding reciprccating movement, similar to the reciprocations provided by the contact cams on the standards and gear, respectively.

As shown in Fig. 5, continual rotation of the metal shell while in engagement with the packine of the suction box against its inner surface, gradually wears parallel circumferential grooves or score marks in such inner surface or wall. This may be due to slight. inequalities in the composition of the packing strips, or to slight accumulations on the packing, at various points, of fine grit or other abrasive sediment. Whatever the cause, the rolls or shells very generally do wear irregularly, or score circumferentially, in constructions where there is no relative longitudinal movement between the roll and the suction box. On a considerably enlarged scale, this is shown inFig. 5 in which the metal has been cut or scored out from the grooves or channels 16 while still remaining in the ridges or ribs 17, between.

But, by maintaining constant or periodic relative longitudinal movement between the inner shell surface and the contacting packing strips, such surfaces as would tend to produce the grooves 16 are continually moving back and forth lengthwise, so that they operate to uniformly and evenly distribute the wear throughout the inner surfaces of the shell, completely eliminating all scoring or grooving, and leaving a perfectly smooth wall of uniform interior diameter throughout. By

. wall of said roll,

such reciprocation the wear is so distributed that the entire inner surface is evenly cut or ground down to the same uniform depth, leaving neither groove nor rib, but an even, smooth and uniform surface.

In the form shown in Figs. 7 and 8 oppositely acting inclines 100 on the faces of the gear, in contact with small rollers or the like 101 carried by the adjacent bearings, W111 act to reciprocate the shell, as will be understood. Or, to state it slightly differently, the gear, instead of extending in a plane perpendicular to the longitudinal axis of the roll, extends in a plane at an incline to it. The gear is so positioned on the shell as to allow a slight space between each face and the adjacent bearing face when in its nearest position of approach thereto, the maximum space being appreciably greater. In this way, free reciprocation of the shell is possible without actual engagement between the faces of the the bearings.

It is hardly necessary toystate that the distance which'the shell or box is moved, relatively to the other, does not need to be more than one half the distance between centers of adjacent perforations in the same longitudinal row. The two forms herein disclosed are purely illustrative .of the general idea of the invention and it is not intended to in any degree limit the invention exactly to them but to include any and all constructions falling fairly within the scope and intent of the appended claims.

aving described my invention, what I claim and desire to protect by Letters Patcut is:

1. In combination, a revoluble suction roll, a suction box mounted within the same and in free traveling contact with the inner wall of said roll, and means for causing relative longitudinal movement between said roll and box.

2. In combination, a revoluble suction roll, a suction box mounted within the same and in free traveling contact with the inner wall of said roll, and means for causing relative longitudinal reciprocation between said roll and box.

3. In combination, a revoluble suction roll, a suction box mounted Within the same and in free traveling contact with the inner and means engaged by said roll for causing relative longitudinal movement between said roll and box.

4. In combination, a revoluble suction roll, standards for supporting the same, a suction box supported within said roll and in free traveling contact with the inner wall of said roll, and coacting elements carried by said roll and said standards for causing relative longitudinal movement between said roll and box.

5. In combination, a revoluble suction gear and the faces of roll, standards for supporting the same, a suction box supported within said roll and in free traveling contact with the inner wall of said roll, cams carried by said standards 5 and cooperating means carried by said roll and adapted to engage and actuate said roll longitudinally relatively to said suction box. 6. In combination, a revoluble' suction roll, standards for supporting the same, a suction box supported within said roll and in free traveling contact with the inner wall of said roll, an eccentric carried by one of said standards, and means carried by said roll and adapted to be engaged by said eccentric to actuate said roll longitudinally, and means for actuating said eccentric through the rotation of said roll.

7. In combination, a revoluble suction roll, standards for supporting the same, va suction box supported within said roll and in free traveling contact with the inner wall of said roll, oppositely acting eccentrics carried by said standards, means carried by said roll and adapted to be engaged by said eccentrics to actuate said roll longitudinally, and means for actuating said eccentrics through the rotation of said rolL 8. In combination, a revoluble suction roll, standards for supporting the same, a suction box supported within said roll and in free traveling contact with vthe iner wall of said roll, oppositely acting eccentrics carried by said standards, means carried by said roll and adapted to be engaged by said eccentries to actuate said roll longitudinally, a common shaft for actuating said eccentric and means for actuating said shaft through the rotation of said roll.

9. In combination, a revoluble suction roll, standards for supporting the same, a suction box supported within said roll and in free traveling contact with the inner-wall of said roll, oppositely acting eccentrics carried by said standards, means carried by said roll and adapted to be engaged by said eccentrics to actuate said roll longitudinally, a shaft for actuating each eccentric and provided with a gear, a common drive shaft provided with gears meshing with and driving each of the aforesaid gears, and meansfor actuating said driving shaft through the rotation of said roll.

Signed at Sandusky, Ohio, this 7th day of- August, 1928.

HILAND R. FARNSWORTH. 

